Pneumatic clutch control device



' Nov.y 16, 1937. G. c. FARMER 2,099,422

PNEUMATIC CLUTCH CONTROL DEVICE FiledJan. 9. 193e s sheets-sheet 2 INVENfoR GEORGE C. FARMER BY M. i

Nov. 16, 11937. G. c. FARMER PNEUMATIC CLUTCH CONTROL DEVICE Filed Jan. 9. 1956 5 sheets-sheet 3 LEFT 4 5 SELFAPP/NG INVENTOR GEORGE C. FARMER BY MAW@ ATTORNEY lPatented Nov. 16,1937

aoaaizz APli'rswr OFFICE rNnUMA'rIc CLUTCH coN'raoL mivlcli:

George C. Farmer, Chicago, Ill., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania 4Application January 9, 1936, Serial No. 58,352

I 13 claims. (Cl. 303-6) This invention relates to fluid pressure operated means adapted to be employed to. control a clutch device. f n f In certain types of apparatus, such-as power 5 operated shovels, power driven means are provided to control parts ofthe apparatus, and, in order to control movement of these parts of the apparatus, as well as'to eilect movement thereof in either direction, clutch means are provided to connect the driving means to the driven means so as to drive the driven meansfi'h either direction. In order to secure flexible operation ofthe apparatus the clutch means'may be'constructed so that the rate at which the driven means is driven by the driving means may be varied by varying the force employed to effect engagement of the clutch means.

It has been proposed heretofore to employ fluid pressure operated means to effect movement of the clutch means to the driving positions, and y thereby effect driving of the driven means in either direction, or to control movement of the clutch means to the neutral position, in which the Y driven means is not ldriven by the driving means.

In the systems heretofore provided,however,`it is difficult or impossible to control the supply of fluid under pressure to and the .release of fluid under pressure from the fluid pressure operated means so as to secure smooth or graduated engagement of the* clutch means, and it is diiicult or impossible, therefore, with these systeins to secure smooth or accurate operation of the apparatus. VIn addition; -in the systems heretofore providedit isv impossiblefor an operator to ascertain, other than byV observing operation of the apparatus, the pressure of the fluid supplied to the fluid pressure operated means, and, therefore, the degree of engagement -of the clutch device which is secured. l. s. Itis the 'principal object of this invention to provide animproved pneumatic clutch control system.A

A fluther object of the invention is to provide an improved pneumatic clutch control system in which the pressure of the iluld supplied to-the clutch actuating means may bev accurately controlled r varied, whereby the degree of'clutch engagement secured may be accurately graduated.

501' `Another objectof the invention is to provide an improved pneumatic. clutch control system havingga manual control member, and having means subject to the pressure of the iiuid sup;- pliedto the clutch actuating means for opposing movement of the manual control member to its ,the rotary valve of the selectorl valve device emapplication positions, whereby the operator is constantly informed of the pressure of the uid supplied to the clutch actuating means, and thereby. is informed of the degree of clutch engagement which has been secured. 5

Other objects of the invention and features of novelty will be apparent from the following description Itaken in connection with the accom-- panying drawings, in which,

Fig. 1 is a diagrammatic view, partly in. section, 10

of a clutch control system embodying my invention,

`Fig; 2 is an enlarged sectional view taken substantially along the line 2-2 of Fig. 1, Y

Fig. 3 is an enlarged sectional view taken sub- 15 stantially along the line 3--3 of Fig. 1,

Fig. 4 is an enlarged sectional view taken substantially along the line 4--4 of Fig. 1,

Fig.` 5 is a diagrammatic view of the ports in ployed in the system shown in Fig. 1, 20

Fig. 6 is a fragmentary diagrammatic view, partly in section, of a modified form of the clutch control system embodying this invention,

Fig. 7 is an enlarged sectional view taken substantialiy along the line i---T of Fig. 6, and

Fig. 8 is a diagrammatic view of the ports in the rotary valve of the selector valve device employed in the system shown in Fig. 6.

Referring to Fig. 1 of the drawings, vthe system 30 therein illustrated comprises a clutch device indicated generally by the reference numeral I, uid pressure operated clutch actuating means indicated generally by the reference numeral 3, a selector valve device I, a. pressure regulating valve device 6,- manual operating means indicated generally by the reference numeral 8 for opervating the selector and pressure regulating valves,

and`fiuid pressure responsivemeans I0 for controlling the movement of the manual operating 4() The clutch device I comprises a' driving member 20, mounted on a driving shaft 2 i, and positioned vbetween the -driven members -22 and 24, which have connected thereto apparatus, not shown, to 45 be driven, while the driving shaft 2i is driven by' suitable driving meansnot shown.

'I'he driving member 20 is secured on the driving shaft 2| so as to be rotated thereby, but ,g also so as to' be movable axially thereon. 'I'he 50 driving member 20 has formed on one end thereof a conical friction surface 26, which isi adapted to engage a complementary friction surface 2B formed on the driven member 22. The driving member 20 hasvformed onv the other end thereof 55 a similar conical friction surface 30 which is adapted to engage the friction surface 32 formed on the driven member 24. l j

The fluid pressure actuating means 3 for the clutch device comprises a cylinder 35 having a bore therein in which is mounted a piston 31, which has at one side thereof a chamber 39, and at the other side lthereof a chamber 40.

The piston 31 has a piston rod 42 secured thereto and this rod extends through an end of the wall of the cylinder, the opening through packing 43, which is held in place by means of a pack nut 45. The piston rod 42 also extends through, and is supported by, a bracket 46.

'I'he piston rod 42 has interposed therein a yoke 50, which carries a pin 52, which extends through an elongated slot 53 in the end of the lever 55which is pivotally supported on a bracket 58 by means of a bolt 56.

The lower end of the lever 55 is forked, and the tines of the forked portion are disposed on opposite sides of the driving member 20. 'Ihe ends of the tines have elongated openings or slots v59 formed therein, through which extend the pins or bolts 6| associated with a collar 64, which isv secured in an annular groove formed in the driving member 20.

The selector valve device"4 comprises a casing having a valve chamber 66 therein which is constantly connected by way of a pipe 69 with a suitable source of fluid under pressure, such as a reservoir 10. 'I'he valve chamber 66 has mounted therein a rotary valve 12 which is adapted to be operated by means of a shaft 14 having a lever 16 secured thereto'. 'I

'I'he pressure regulating valve device 6 is of the self-lappingtype and comprises a movable abutment in the form of a diaphragm 80, which is subject to the opposing pressures of the fluid in a chamber 82 and of a spring 84, one end of which engages an adjustable member `86, and the other end of which engages a spring seat 88 which has a conical recess 90" formed in the Vface thereof into which extends the end of' a stem 92`which is secured in an opening in the center of the diaphragm 80.

The adjustable member 86 has internal threads 94 formed thereon which are adapted to cooperate with external threads 96 formed on the` casing section 98. The member 86 has secured thereto'a lever |00, and, as is best shown in Fig. 1 of the drawings, a tension spring |02 extends between the lever and an arm |03 formed on the casing section 98 and yieldingly urges the lever |00 into engagement with a stop associated with the arm |03.

The stem 92 has a rounded end |05 formed thereon which' extends into a recess formed in the lever |01 which engages the supply valve ||0 and the discharge valve ||2.

44The supply valve ||0 is mounted in a chamber |I5, and ls urged into engagement with its seat by means of a spring I6 lacting through a spring seat ||8. The `chamber is connected to the reservoir 1,0 by way of a pipe and passage |20.

The discharge valve ||2 is mounted in a bore in the casing section |22 and is yieldingly urged away from its seat |26 by means ofL a spring |24, which is proportioned so as to be substantially weaker than the spring ||6 associated with the supply valve ||0.

Themanual operating means 8 comprises a; lever |30, which is pivotally supported on a bracket |32 by meansof a pin |34, and is cony:rosanna x6 by means of a pin |42, While the other end of the. link is forked or divided and the portions thereof .are located on opposite sides of the lever |30 and have` elongated openings or slots |44 therein into which extends the Apin |36. which the rod extends being sealed by means of l the lever |00 by means of the pin |42, and has A link |46 has one end thereof secured to its other end forked or divided and the portions thereof .are positioned on opposite sides of the lever |30 and have elongated openings or slots |48 therein into which extends the pin |38.

IIfhe fluid pressure responsive means I0 comprises a movable abutment in the form of a diaphragm |50, which is clamped between the casing sections |52 and |54, and has secured' thereto a link |56,` which is connected to the lever |00 of the pressure regulating valve device 6 by means 'of the pin |42. The casing section |52 is pivotally supported from the bracket l32 by'means of the pin |34 and cooperates with the diaphragm |50 to form a chamber |58, which is connected by way of a exible conduit |60 with the pipe I6 i, which communicates with the chamber 82 of the pressure regulating valve device 6 and with a port in the seat of the rotary valve 12 of the selector valve device 4.

The apparatus is shownin Fig. 1 of the draw-- ings in the neutral position, in which position the driving member 2i is out of engagement with the driven members, 22 and 24, while the piston 31 is located adjacent the mid portion of the bore in the cylinder 35.A

The operating leve'r |30 is shown in the neutral position, and when itis in'this position, the spring |02 holds the lever |00 of the pressure regulating valve device 6 in engagement with the arm |03. When the lever |00 is in this position the spring 84 is permitted to expand toits full length, so that no pressure is exerted by this spring on the diaphragm 80,.thereby permitting 1 the spring ||6 to hold the supply valve ||0 in the seated position to cut off the supply of fluidv under pressure to the chamber 82, and also permitting the spring |24 to hold the discharge valve I2 away from the seat |26 and thus connect the chamber 82r to the4 atmosphere.

`When the operating lever |30 is in the neutral positionthe rotary valve 12 of the selectorfvalve device 4 is held in a position in `which the ports in the rotary valve establish communication between. an atmospheric passage |66 vand a port communicating with a pipe |62, which communicates with the chamber 39 at a point adjacent one A end of the bore in the cylinder 35, and a port associated with the pipe |64, which communicates with the chamber ||0at a point adjacent the other end of the cylinder 3'5.

In additiominthis position of the rotary valve 12 the port in the seat of the rotary valve associated with-the pipe |12 is lapped. The pipe |12 is provided with branches which communicate with'the cylinder 35 at points on opposite sides of the mid portion-of the cylinder. The branches of the pipe |12 have ball check valves indicated at |10 and |14 interposed therein and operative to permit fluid to ilow from the cylinder to the pipe |12, and to prevent the iiow of iluid from the pipe |12 to the cylinder.

The ports through which fthe branches of the thickness of the vpiston 31 so that when the piston is in its neutral position, it is located between.

these ports, and one branch oi the pipe |12 communicates with the 'chamber on one side of the piston, While theother branch of the pipe |12 communicates with the chamber on the othe side of the piston.

When it is desired to operate the clutch device so as to cause the driving member to drive the driven member 24 the lever |30, is moved in a counterclockwise direction from the neutral `posio f tion, which is the position indicated by the broken line identified by the numeral 3, to a point in the right application self-lapping zone. When thel lever |30 is moved to this point the link |35 is moved to the right, as viewed in Fig. 1 of the drawings, and the rotary lvalve 12 of the selector valve device 4 is turned to a position in which a y port in the rotary valve establishes communication between the pipe |6|1 leading from the pressure regulating valve device 6, andthe pipe |64, j which communicates with the chamber 40 of the4 cylinder 35. In addition another port in the rotary valve 12 establishes communication between the pipe |62, which communicates with the chamber 39 of the cylinder 35, andv the atmospheric exhaust passage |66, 'while the port in the tseat of the rotary valve which communicates with the pipe |12 is lapped.

On movement of the lever |30 in a counterclockwise direction, as viewed in Fig. 1 of the drawings, the pin |38 moves freely to the right in the slots |48 in the ends of the link |46, while the pin las moves te the left hand ends ef the slots |44 in the link |40; andv thereafter, onfurther movement ofthe lever |30 Ain a counterclockwise-direction, the link |40 is moved to the left, as viewed in Fig. 1 ofthe drawings, and causes the lever v|00 to be rotated-ina counterclockwise direction against the spring |02. I

On movement of the lever |00 in a counterclockwise direction the threads 94 on the adjusting member 86advanceon the threads 96 on the 4casing section 98, thereby causing the adjusting inember 86 to compress the spring 84. When the spring 04 is compressed the diaphragm 80 is biased downwardly and the stem 82 presses upon the lever |01 and forces itodownwardly.

One end of the lever I 01 engages the end of the stem of the supply valve H0, which valve is held in theseated position by means of the relatively strong spring ||6, While the other end of the lever |01 engages thedischarge valve ||2, which is held in the' open position by a relatively weak spring |24. On the initial downward movement of the lever |01 the supply valve I0 remains in the seated position and the discharge valve I2 is moved against the spring |24 until the valve engages the seat l|26, andcuts olf communication between the chamber 82 and the atmosphere, and on further downward movement of the lever |01 the supply valve ||0 is moved away from its seat against the spring I6.

Fluid under pressure from the reservoir 10' which is supplied through the pipe |20 to ythe chamber ||6 may thereupon 4flow to the chamber 82, from which it ows by way of the pipe"|6| to vthe selector valve device 4, .and Ltherefrom throughthe port in the rotary valve 12 to the pipe |64 which leads to the chamber' 40 of the cylinder 85, andon an increase in the pressure.

of the fluid in this chamber the piston 31'is moved to the left as viewed in Fig. 1 of the drawings.

cannot 'flow therefrom to the chamber 3.9 on the other side of the piston 31 as ow in this direction is prevented by the ball check valve |10.'

Flui'dwhich iseupplied te the pipe |12 cannot scape therefrom tothe atmosphere atthis time 'as -the port in the seat of the rotary valve is lapped, a-nd the pressure of the fluidin the pipe |12 will build up as the-pressure of the fluid in .the chamber 40 increases.

On movement of the piston 31.`to the left the pist-on rod '42 is moved, and the piston rod acting through the yoke 50 Aand the pin 52 causes the lever 55 to Lturn in a counterclockvvise direction about the axis. determined by the pin 56, thereby moving the lower end of the lever 55 to the right, as `viewed in Fig. 1 of the drawings. The-lever 55 acting through the collar '64 moves the driving member 20 on the driving shaft-2|, and presses the frictionsurface 30 on the driving member 20 into engagement with the friction surface 32 on the driven member-24.

'The rate 'atfwhich the driven member 24 is driven by they, driving member 20 isdependent upon the force employed to -press the friction surface 30 into-engagement with the friction surface 32. This force is determined by the pressure of 40 is regulated by means of the pressure regulating valve device 6.

On yan increase in the pressure of the fluid in the chamber 82, which pressure will be substantialiy the'samev as the pressure in the chamber.

40 of the cylinder 35, the diaphragm 80 will be moved upwardly against the spring 84. On this movement of the diaphragm the supply valve ||0 is moved by the lspring ||6 toward the seated position, and the lever |01 Will be pivoted about the end of the stem 02-so as to maintain the discharge valve ||2 in engagement with its seat |26.

When the pressure of the fluid in the chamber 82 has increased to a value high enough to move the diaphragm l80 4against the spring 84 yan amount suflioient-to permit the supply valve ||0 vto be moved to the seated-position by means of the spring H6, the supply of fluid to the chamber 82W|1l be out off; thereby cutting off the further increase in the pressure of the fluid in the chamber 82, while the pressure of the fluid in this chamber will be maintained as the dischargel valve ||-2 is in the seated position. y The pressure to which the fluid in the chamber 82 mustlincrease in order to overcome the spring 84 depends 'upon' the extent to which the spring 84 has been lcompressed, which is determined by the amountiof movement of the lever |30 away from the neutral position. The farther the lever |30 is moved from the neutral position, the farther the spring 84 will becompressed and the greater-will be the force exerted by the spring .on the diaphragm 80, and hence the'higherthe .pressure to which the fluid in the chamber 82 must build up before the diaphragm 80 is moved against the spring 84 an .amount suillcient to permit the supply valve ||0 to be moved to the seated position to cut offthe supply ofl fluid t the chamber 82. 1- If, while the driving member 20 is in engagement with the driven member 24, the operator desires to increase the degree of clutch engagement he may do so by moving the lever |30 farther chamber. When the pressure of the uid in the chamber 82 has increased to a value such that "the force exerted by the iiuid on the diaphragm 80 again overcomes the opposing force of the spring 84, the diaphragm 80 wili be moved against the spring 84 and the supply valve |I0"will be again moved tothe seated position by the spring I I6 to prevent the further supply of fluid ,to the chamber 82.

' On an increase in the pressure of the fluid in the chamber 82 a similar increase will be eiected in the pressure of the fluid in the chamber 40 of the cylinder 35 as the rotary valve 12 of the selector valve device 4 maintains the communications described in detail above throughout the entire range of movement of the operating lever |30 in the right application self-lapping zone.

On an increase in the pressure of the fluid in the chamber 40 a greater force will be exerted on the piston 31 by the iiuid in this chamber, and

` there will be a corresponding increase in the force exerted through the lever 55 to press the driving` member 20 into engagement with the driven member 24.

If, while the drivingmember 20 is in engagement with the driven member 24, the operator desires to decrease the degree of application of the clutch device, he may do so by moving the operating lever |30 in a clockwise direction to a point in the right application self-lapping zone nearer the neutral position.

still maintain the communication between the pipe 62 and the atmospheric exhaustpassage |66,

and also between the pipe 6|, leading from the pressure regulating valve device 6, and the pipe |64, communicating with the chamber 40 of the cylinder 35.

On movement of the operating lever |30 in a clockwise direction the pin |36 is moved toward the right, as viewed in Fig. 1 of the drawings, thus relieving the tension on the link' |40, and thereby permitting the lever to be moved in a clockwise direction by the spring |02 so as to maintain the ends of the slots |44 in engagement with th pin |36. l

On this movement of the lever |00 the adjusting member 86 of the pressure regulating valve device 6 is turned on the thread 96 so as to relieve "the pressure on the spring 84.

On a reduction in the pressure exerted by the spring 84 on the diaphragm 80, the fluid in the ,is moved about an axis formed by the end of the stem of the supply valve ||'0 by the spring |24,A

associated with the discharge valve |I2, which moves the discharge valve I2 away from the seat Fluid under pressure will thereupon be permitthence to the atmosphere. H `the chamber 40 to the pipe |12 past the ball check.

'from the neutral position, thereby moving the ted to escape from the chamber 82, and also from the chamber'40 ofthe cylinder 35, which is connected to the chamber 82 by way of the pipes |64 On a reduction. in the pressure of the fluid in the chamber 82 to a predetermined value, dependent upon the amount of reduction in the compres-l sion of the spring 84, the force exerted by the fluid in the chamber 82 will be insuicient to maintain the diaphragm 80 against the spring i 84, and the spring thereupon will move the diaphragm'downwardly. On this movement of the diaphragm 80 the lever |01 will move about the axis determined by the end ofthe `stern of the supply valve 0, which is held seated by the spring ||6, and the discharge valve` H2 will be moved against the spring |24 into engagement with its seat |26 to cut olf the further release of fluid under pressure from the chamber 82.

As a result of the reduction in the pressure of the uid in the chamber 40 there will be a reduction in the force exerted by this fluid on the piston 31, and there will be a corresponding reduction in the force exerted by the piston 31 through the lever 55 to holdQshe driving member 20 in engagement with the driven member 24.

If, while the driving member 20 is in engagement with the driven member 24, the operator desires to disengage the clutch elements and d iscontinue driving of the driven member 24he may cause the driving member to be moved to the intermediate or neutral position by moving the `rotary valve 12 will be moved to a position to cut off communication between the pipe |62 and the atmospheric passage |66.

In addition, at this time a port in the rotary valve 12 establishes communication between* the chamber 66, which is supplied with iiuid under pressure from the reservoir 10, and the pipev |64.

'Ihis port has a choke |80 interposed therein to' restrict the rate of flow of fluid to the pipe |64 and thereby to the chamber 40. Another port in the rotary valve 12 establishes communication between the chamber 66 and the pipe |62 in this position of the rotary valve, and this port has a choke I8| interposed thereinto restrict the rate of flow of fluid to the pipe |62 and thereby to the chamber 39; l

In this position of the rotary valve 12 a port therein establishes 'communication between pipe |12 and the atmospheric passage |66, with the result that fluid underpressure present in the chamber 40 may iiow therefrom past the ball check valves |10 and |14 to the pipe |12 and Fluid may flow from valve |10 at this time as `the piston is at the left hand end of the cylinder 35, thereby/ establishing communication between the chamber 40 and the lpipe |12 through the passage controlled by the at a substantial value by the supply of iiuid thereto through the pipe |64 at'this time as the flow of fluid to the pipe |64 is restricted to a very slow rate by the choke |63, and this rate is less rapid than the rate at which uid may be released from the chamber 40 through the pipe` |12.

Fluid which is supplied to the pipe |62 ilows therethrough to the chamber 39, and on an increase in'the pressure of fluid in this chamber the aooadaa while th'e pipe |12 is lapped in this position oi the piston 31 is moved to the right, as viewed in'Fig. 1

oi the drawings, thereby moving the piston rod 42 to the right and causing the lever 55 to be rotated in a clockwise direction. This movement of the lever 55 causes the driving member 20 to be moved away from the driven member 24.

When the piston 31 has moved to a position substantially intermediate the ends of the cylinder 35 it opens communication between the chamber 39 and the passage communicating with the branched pipe |12 and controlled by the ball check valve |10.

On movement of the piston 31 to the position to establish communication between the chamber 39 and the branched pipe |12, iiuid from the chamber 39 flows past the ball ,check valve |10 and to the atmospherev through the pipe |12, which at thistime is connected to the atmosphere through a port in the rotary valve 12 and the atmospheric passage |66.

If, after the piston 31 has moved to a position to establish communication between the chamber 39 and the branched pipe |12, the piston continues to move to the right, as viewed in Fig. 1 ofthe drawings, it will cut of! communication between the chamber 40 and the' branched pipe |12 through the passage controlled by the ball check valve |14, thereby cutting off the release i uid under pressure from the chamber 40. As fluid under pressure'is/supplied to the chamber 40 at a restricted rate at this time, the pressure of the iiuid in the chamber 40 will increase and will return the piston to the position intermediate the ports through which the branched pipe |12 communicates with the cylinder 35. On movement of the piston 31 to this position lcommunication is established between the chamber 40 and the branched pipe |12 through the port controlled by the ball check valve |14, thereby releasing iiuid from the chamber 40 and reducing the force tending to move the piston 31 to the left.

If the piston 31 travels too far on this return movement it will cut oil? communication between the chamber 39 and the branched pipe |12 through the port controlled by the bali check valve |10, and as iluid under pressure is -being supplied to this chamber there will be an increase in the pressure of the uid in the chamber 39, and the piston will be returned to the position intermediate the ports leading to the branched pipel |12, so as to establish communication between the chamber 39 and the branched pipe |12 and thereby release the iiuid under pressurepresent in the chamber 39.

Afterthe operating lever |30 4has been in the right return position for a limited period, which is the position indicated lby thebroken line identied by the numeral -2, the operator then moves ythe lever |30 to theneutral position. On this movement of the lever |30 the rotary valve 12 of the selector valve device 4 is moved to a position to cut oi communication between the chamber 66 and the pipes |62 and |64 and to establish communication between the pipe |62 and the atmospheric passage |66, and also between the pipe |64 and the atmospherick passage v166. The chambers 39 and 40 on opposite sides of the piston 31 are, now both connected to atmosphere,

rotary valve 1 In addition, on movement of the operating lever |30 from the right self-lapping application zone to a point adjacent the neutral position, the pin |36 is moved tothe right, as viewed in Fig. 1 o! the drawings, so as to release the link |40 and permit, the spring |32- to move the lever |00 into engagement with the arm |03.

On'movement of the lever |00 into engagement with the .arm |03 the adjusting member 36 isV rotated on the threads 96 so as to relieve the spring 04 of all compression.

On this reduction in the degree of compression of the spring 04 the diaphragm 80 is moved upwardly by the fluid under .pressure in the chamber a clockwise direction to a position in the left application self-lapping zone. 0n this movement of the lever |30 the pin |36 movesireely in the smts m in the link un, while the pin las, after a limited amount of movement of the'lever |30 in a clockwisel direction, engages the ends of the slots |40 in the link |46, so that on further movement of the lever |30 the link |46 is moved to the left, as viewed in Fig. 1 oi the drawings, thereby moving the lever |00 in a counter-clockwise direction against the spring |02.

'Ihis movement of the lever |00 causes the adjusting member 86 to advance on the threads 96 so as to compress the spring`84 of the pressure regulating valve device 6, andthereby cause this valve device, as described in deta above, to supply iiuid under pressure to the pipe |6| at a pressure determined by the amount of movement of the lever |30 awayi'rom the neutral position.

In addition, on movement of `the operating lever |30 to a position in the left application vself-lapping zone the lever 16 of the selector therein establishes communication between the pipe |64, which leads from the chamber 40 of the cylinder 35, and the atmospheric passage |66, while the port associated with the pipe |12 is lapped.` 5 i 4 Fluid supplied to the chamber 39 flows therefrom past the ball check valve |10 to the pipe |12, but as the port in the seat of the rotary valve 12 to which this pipe is connected is lapped at this `time iluid supplied to this pipe will not escape to the atmosphere. The iiow of fluid from the pipe |12 to the chamber 40 is prevented by the ball check valve |14. On an increase in the pressure of the uid in the chamber 39, therefore, the pressure of the build up.

0n movement of the piston 31 to the right the pistonrod 42 is also moved to the right and" causes the lever 55 to move in a clockwise direc- 6 tion about the pin 56, and the. lever 55, acting through the collar 64, moves the driving member 20 to ther left on the driving shaft 2| and presses the friction surface 26 on the driving member 20 into engagement with the friction surface 28 on the driven member 22.

The degree of clutch engagement between the drivingmember 20 and the driven member 22 will depend upon the pressure of the fluid supplied by the pressureregulatin'g valve device 6 to the chamber 39, as explained in detail' above, and the degree of application may be varied by varying the degree of pressurein the chamber 39, which may be accomplished by moving the operating lever |30 towards or away from the neutral position within the left application self-lapping zone. This movement of the operating lever |30 varies the adjustment of the spring 84 of the pressure regulating valve device 6, as explained in detail above.

If while the driving member 20 is in engagement with the driven member 22 the operator desires to disengage the clutch elements and to discontinue driving of the driven member, he may cause the driving member to move to the intermediate or neutral position by moving the operating lever |30 in a counterclockwise direction from its position in the left application selflapping zone to the left returnposition, which is the position indicated by the broken line identiiied by the numeral 4. v

On movement of the operating lever |30 to the left return position the rotary valve 12 of the selector valve device 4 is moved to a position in which communication between the pipe |6| and the pipe |62 is cut oil', and in which communication between the pipe |64 and the atmospheric passage .|66 is also cut oi.

In this position of the rotary valve 12 a port therein establishes communication between the chamber 66, which is supplied with duid under pressure from the reservoir 10, and the pipe |62.

This port has a choke |82 interposed therein to restrict the rate of flow of iiuid-to the pipe |62 and therethrough to the chamber 39 on the face of the piston 31. In addition, in this) position of the rotary valve 12 a port therein establishes communication between the chamber 66 and the pipe |64. This port has a. choke |83 interposed therein to restrict the rate of flow of uid to the pipe |64 and 'therethrough to the chamber 40 on the face of the piston 31.

In addition, in this position of the rotary valve 12 a port therein establishes communication between the pipe |12 and the atmospheric passage |66, with the-result that fluid under pressure present in the chamber 39 may iiow past the ball check valves |10 and |14 to the pipe |12 and therefrom to the, atmosphere. Fluid may flow from the chamber`39 to the pipe |12 past the ball check valve |14 at this time as the piston 31 is in the extreme right hand position, in which position communication is established between the chamber 39 and the port controlled by the bali check valve |14.

As a result of the release ofv uid under presi-.k`

sure from` the chamber 39 Athrough the pipe |12 there will be a reduction in the pressure of the fluid in this chamber, and this pressure will not be maintained at a substantial valueby the supply of fluid thereto through the' pipe |62 at this time as the flow of iiuid to the pipe |62 is restricted to a slow rate by the choke |82, and this rate is less rapid than the rate at which fluid crease in the pressure of the fluid in this cham-z ber, the piston 31 is moved to the left, as viewed in Fig. 1 of the drawings, thereby moving the piston rod 42 to they left and causing the lever 55 to be rotated in a counterclockwise direction. This movement of the lever 55 causes the driving member 20 to be moved away from the driven member 22.

When the piston 31 has been moved to a position substantially intermediate the ends of the cylinder 35 it uncovers the passagebetween the chamber and the pipe |12 controlled by the ball check valve |14, so as to permit fluid from the chamber 40 to iiow past the ball check valve |14 to the branched pipe |12, and therefrom to the atmosphere.

If after piston 31 has moved to a position to establish communication between the chamber 40 and the branched pipe |12, the piston continues to move to the left, as viewed in Fig. 1 of the drawings, it will cut ofi communication between the chamber 39 and the branched pipe |12 through the passage controlled by the ball check valve |10, thereby cuttingK off the release of fluid under pressure from the chamber 39. As uid under pressure is supplied tothe chamber 39 at a restricted rate at this time, the pressure of the uid in the chamber 39' will increase and the iiuid in this chamber acting on the piston 31 will return the piston to the position intermediate the ports through which the branched pipe |12 communicates with the cylinder 35. On

movement of the piston 31 to this position communication is established between the chamber 39 and the branched pipe |12 through the port 31 to the right.

If the piston 31 travels too far on this return movement it will cut off communication between the chamber 40 and' the branched pipe |12 through the port controlled by the bou check valve |14, and, as fluid under pressure is being supplied to this chamber, there will be an increase in the pressure of the fluid in the chamber 40 and the piston` 31 will be "returned to the position intermediate the ports leading to the branched'pipe |12, so as to establish communication between the chamber 40 and the branched pipe |12 and thereby permit the uid in the chamber 40 to escape to the atmosphere through the pipe |12. f.

After the operating lever-|30 has been in the left return position for a short time it is moved to the neutral position, and on this movement of the lever |30 the rotary valve 12 is returned to the position in which it-is`shown'in Fig. 3 of the drawings, in which position ports in the rotary valve establish communication between the pipe |62, and thepipe |64, and the atmospheric passage |66 so as to connect the chambers on opposite sides of the piston 31 to the atmosphere.

'On movement of 'the lever |30 to a position-adjacent the neutral position the lever |00 of the pressure regulating valve device 6 is moved by the spring |02 intoA engagement with the arm |03, in which position of the lever v|03 all pressure on the spring 84 is relieved, with the result that the valve device 6 operates, as described in detail` above, to release the uid under pressure present in the chamber 82 and in the pipe |6|.

The clutch :control device provided by this invention incorporates means to keep the operator constantly informed of the pressure voi the fluid supplied by the-pressure regulating valve device 6 to the cylinder 35 to effect engagement of the clutch means, and thereby inform the operator of the degree of clutch engagement secured. This means comprises the iuid pressure responsive means I0, which is subject to the pressure of fluid supplied by the pressure regulating valve device 6 to the cylinder 35 to effect engagement of the clutch means.

On the supply of fluid under' pressure to the pipe |6| uid flows therefrom by way offthe ilexible conduit to the chamber |58 and presses the diaphragm |50 to the right, as viewed in Fig. 1of the drawings. The force exerted by the fluid in the chamber |58 on the diaphragm |50 is transmitted through the link |56 to the pin |42 and urges this pin in a'clockwise direction'.

The force exerted on the pin |42 is transmitted throughone of the links |40 or |46, depending upon the'position of the operating lever |30, to the' operating lever |30, and tends to move this lever towards the neutral position.

The force exerted by the fluid under pressure in the chamber |58 on the diaphragm |50 wi11 vary in accordance with the pressure of the fluid supplied to the pipe IGI, and the operator is,

therefore, constantly informed .of the pressure conditions present in the cylinder 35.

llin Figs. 6 to 8 inclusive of the drawingsthere is illustrated, in part, a modied form of the equipment embodying this invention. This equipment is similar to that shown in Fig. 1 of the drawings, but differs from that shown in Fig. 1 of the drawings in that in place of the branched vpipe |12 employed in the equipment shown .in Fig. 1, separate pipes |12a rand |12b are employed, and4 each of these pipes is connected to a port in the seat of the rotary valve 12a of the selector valve device 4a.

The pipes |12a and |12b communicate with the bore in the cylinder 35a through ports which are located adjacent the mid portion of the cyl- `inder and are spaced apart a'distance slightly ,'when the operating lever |30 is in the vneutral side of the piston 31. As the pipes |62aand |64a,

are connected to atmosphere', the chambers 39a and 40a on opposite sides of the piston 31 are connected to atmosphere.

` When the operating lever |30 is in the neutral position the rotary valve 12a laps the ports associated with the pipes |12a and |12b.

When the voperating lever |30 is moved to the right application self-lapping zone the-rotary -valve 12a is turned to a position in which it laps the ports associated with the pipes |12a and |12b, and in which a port in the rotary valve establishes communication between the port associated with the pipe |62a andthe atmospheripassage |66a.

In addition, on movement of the rotary valve12a` to this position a port in the rotary valve establishes. communication between'the pipe |6|, leading from the pressure regulating valve device 6, and the pipe Nida,V leading `to the chamber 40a of the cylinder 35a.

On movement of the operating lever |30 to a point in the right application self-lapping zone the pressure regulating valve device 611s conditioned, as described in detail in connection with the system shown in Fig. 1, to supplyy iluid under pressure to the pipe |6| at a pressure determined by the extent of 4movement of the operating lever |30 away from the neutral position.

Fluid under pressure thereupon flows from the pipe |6 to the pipe |6411 and therethrough to the chamber 40a. Fluid supplied vto the .chamber 40a may flow to the pipe |12b, but its flow from the pipe l|1213 is cut oil as the port associated with this pipe is lapped by the rotary valve 12a.

On an increase in the pressure of the fluid in the chamber 40a the piston 31 moves to the left, as viewed in Fig. 6 of the drawings, to effect movement of the clutch driving member 20 into engagement with the driven member 24.

After a predetermined amount of movement of the piston 31 to the left it moves beyond the port associated with the pipe |12a, thereby establishing communication between the cha the pipe |12a. Fluid under pressure in the chamber 40 will thereupon flow to the pipe |12a, but it cannot escape from this pipe as the port associated with this pipe is lapped by the rotary valve 12a in this position of the rotary valve.

When the operator desires to release the clutch smeans and to return the driven member 20 to the mber 40 and intermediate position he may do so by moving f the operating lever |30 to the right return position, which is the position indicated in Fig. 8 by the atmospheric passage |6611, thereby releasing the uid under pressure present in the chamber 40a, while-a port in the rotary valve 12a connects the .pipe |12a with the atmospheric passage |66a.

At the same time a port in the rotary valve 12a, having a choke or restricted portion |80a therein 'establishes communication between the chamber 66a, which is supplied with uid under pressure from the reservoir 10, and the pipe |6 2a, leading to the chamber 39a, so that iiuid under pressure is supplied at a restricted rate from the reservoir -10 to the chamber 39a.

In addition, in this position of the rotary valve 12a a port therein establishesy communication between the chamber 66a and the pipe Al64a leadto the chamber 40a on the face of the piston driving member 20 away from .the driven member 24.'

When the piston 31 moves to the position in which it is shown in Fig. 6 of the drawings it uncovers the passage between the chamber 39a and the pipe 12a so as to permit fluid to escape from 4the chamber 39a to the atmosphere through the pipe |12a.

If the piston 31 continues to move to the right and moves beyond the position between the ports through which the pipes |1211 and |121) communicate with the bore in the cylinder 35a., the piston will cut oi communication'between the chamber 40a and the pipe |121). As fluid is supplied to the chamber 40a at a restricted rate through the pipe |6411 at this time the pressure of the fluid in the chamber 40a, will increase and the fluid will return the piston 31 to the intermediate position in which communication is established between the chamber 40a. and the pipe |121) so that the fluid in the chamber 40a. is released to the atmosphere through the pipe |121).

If the piston 31 travels too far on this return movement it will cut off communication between the chamber 33a and the pipe |12a, and as fluid is supplied to the chamber 30a at a restricted rate through the pipe .132e atl this time the pressure of the fluid in the chamber 39a will increase and will move the piston 31 to the intermediate position so as to again establish communication between the chamber 39a and the pipe'l12a, and thereby permit the fluid in the chamber 39a, to escape to the atmosphere through the pipe |12a.

After the operating lever |30 yhas been in the right return position for a short time, the operator may return it to theneutral position, and on movement of the operating lever |30 to this position, the rotary/valve 12a of the selector valve device 4a is turned to a position to cut 0E the supply of uid under pressure from the chamber 66a to the pipes |6211 andv |6411. and to connect the pipes |6241. and |3411, to the atmospheric passage 15Go so that the chambers on the opposite sides of the piston 31 are connected to atmosphere.

On movement of the loperating lever |30 to a position adjacent the neutral position the pressure regulating valve device 6 is conditioned to cut oi the supply of fluid under pressure to the pipe |6| and to release the uid under pressure present in this pipe as explained in detail above. When the operator desires to move the clutch driving member 20 into engagement with the driven member 22 he may do so by moving the operating lever |30 in a clockwise direction to the left application self-lapping zone, and when the lever |30 is moved to this position the rotary valve 12a of the selector valve device 4a is turned to a position in which a port therein establishes communication between the pipe |6411. and theV atmospheric passage |6511, so that the chamber 40a is maintained at atmospheric pressure, while another port in the rotary valve 12a establishes communication between the pipe 6| and the pipe |6211., so that fluid under pressure supplied by the pressure regulating valve -device 6, which, on movement of the operating lever |30 is conditioned to supply fluid under pressure to the pipe 16| as explained in detail above, may flow'to the chamber 39a. In this position of the rotary valve 12a the ports associated with the pipe |12a and the pipe |121) are lapped. On the supply of fluid under pressure to the chamber 39a fluid will flow therefrom to the pipe 1121i, but it cannot escape to the atmosphere as the port associated with the pipe |1211 is lapped by the rotary valve 12a.

On an increase inthe pressure of the fluid in the chamber 39a. the piston 3 1 moves to the right, as viewed in Fig. 6 of the drawings, and effects movement. of the driving member 20 into engagementwith vthe driven member 22.

After a predetermined amount `.of movement of the piston 31 to the right it moves beyond the port through which the pipe |121) communicates with the bore in the cylinder 35a, thereby establishing communication between the chamber 39a andthe pipe |12b, Fluid under pressure from the chamber 39a may thereupon flow to the pipe |12b, but it cannot escape therefrom as the po'rt associated with this pipe is lapped by the rotary `valve 12a.

When the operator desires to return the driving member 20 to the intermediate position he may do so by moving the operating lever |30 to the left return position, which is the position indicated by the broken line identified by the numeral 4, and when the lever |30 is moved to this posi- 'tion the rotary valve 12a is moved to a position .to cut off the supply of nuid from the pipe |6| to the pipe |62a leading to the chamber 39a, and also to cut off communication between the pipe |6411` and the atmosphere. In this position of the vrotary valve 12a a port therein establishes com- 12a a port therein establishes communication between the chamber 66a, which is supplied with fluid under pressure from the reservoir 10, and

the pipe |6211 leading to the chamber 39a. This port has a choke |8211. interposed therein to restrict the rate of flow of fluid to the chamber 39a. In this position of the rotary valve 12a another port therein establishes communication between the chamber 66a, and the pipe |6411 leading to the chamber 41011.v This port has a choke |831; intercommunication between the chamber 40a and the l pipe |1217 and thereby permits the fluid under pressure in the chamber 40a to escape to the atmosphere through the pipe |12b,

If the piston 31 moves beyond the position intermediate the ports through which the pipes |12a and |121) communicate with the bore in the cylinder 35a it will cut off communication between the chamber 39a, and the pipe |12a. As uid under pressure is supplied to the chamber 39a at a restricted rate through the pipe |62a at this time the pressure of the fluidin the chamber 39a will build up and the piston 31 will be returned to the intermediate or neutral position. If the piston 31 travels too far on this return movement it will cut off communication between the chamber 40a, and the pipe |1217. As iiuid is supplied tothe chamber 40a, the pressure of the fluid in this chamber builds up when the release of fluid therefrom through the pipe |1217 is cut off and the piston 31 will be returned to the position to again establish communication between the chamber 40a and the pipe |12b and permit the fluid in the chamber 40a to escape to the atmosphere.

. to a position to cut o'f the supply 'of fluid from the After the operating lever 30 has been in the left return position for a short time the operator may return it to the neutral position, which is the position indicated by the broken line, which is identified; by the numeral 3, and on movement of the operating lever |30 to this position the rotary valve 12a of the selector valve device 4a is turned chamber 66a to the pipes |62a and IBla, and in which ports in the rotary valve establish communication between the pipes |62a and |64a and the atmospheric passage |66a so that the chambers on opposite sides of the piston 31 are connected to the atmosphere.

In addition on movement of the operating lever |30 to a position adjacent the neutral position the pressure regulating valve device 6 is conditioned to cut oil the supply of uid under pressure to the pipe |6|, and to release the fluid present in this pipe.

. It will be seen that the clutch control device provided by this invention employs a selector valve device which directs the flow of fluid under pressure to either of the two chambers of the iluid pressure operated clutch actuating means,

depending upon the direction of movement of the operating lever away from the neutral position. In addition, this clutch control device has a pressure regulating valve device which controls the pressure of the fluid supplied to the selected chamber of the clutch actuating means in accordance'with the amount of movement of the operating lever away from the neutral position. The pressure regulating valve device makes it possible for the operator to carefully graduate or control the pressure of the fluid employed to effect engagement of the clutch device, and, therefore, enables the operator to secure smooth, gradual engagement of the clutch, andv to control the degree of engagement accurately.

While two embodimentsof'the improved pneumatic .clutch control device provided by this invention have been illustrated and described in detail, it should be understood that the invention is not limited to these details of construction and that numerous changes and modifications may be made without departing from the scope of the following claims.

Having now described my invention, what I claim as new and desire to secure by Letters Pat-y ent, is:

1. In a control system for a pair of friction clutch elements having associated therewith movable abutment means subject to and operated on an increase in the pressure of the fluid supplied thereto to move said clutch elements into operative engagement, said system comprising valve means for supplying fluid under pressure to said movable abutment means, said valve' means having an actuating element having a normal position, the valve meansy being operative to supply uid under pressure at pressures which vary in accordance with the amount of movement of the said actuating element from the normal position, a manually operable member having a normal position, means for moving the actuating element of the valve means away from its normal position in accordance with movement of the manually operable member away from its normal position, and a movable abutment subject to the pressure of the iluid supplied by the valve means and opposing movement of the manually operable member from the normal position.

2. In a control system for a pair o; friction vary in accordance with the amount of movement of the said actuating element from the normal position, a manually operable `member having a normal position, means for moving the actuating element of the valve means away from its normal position in accordance with movement of the manually operable member away from its normal position in either direction, and a movable abutment subject to the pressure of the fluid supplied by said valve means and opposing movement of the manually operable member away from the normal-position in either direction.

3. In a control system for a pair of clutch devices each comprising a. pair of friction clutch elements, said system comprising movable abutment means subject to the pressure of the uid in chambers on opposite sidesthereof, said abutment'means having a normal position and being operative on movement therefrom in one direction to move the elements of one of said clutch devices into operative engagement and operative on/ movement therefrom in the opposite direction to move the elements of the other of the clutch devices into operative engagement, passages controlled by said abutment through which uid may be released from said chambers to the atmosphere, a valve device having a normal position and being operative on movement from the normal position in either direction to supply fluid under pressure to said chambers at restricted rates.

; 4. In a control system for a pair of clutch devices each comprising a pair off friction clutch elements, said system comprising movable abutment means subject to the pressure of the fluid in chambers on opposite sides thereof, said labutment means having a normal position and being operative on movement therefrom in one direction to move the elements of one of said clutchdevices into operative engagement and operative onL movement therefrom in the opposite direction to move the elements of the other of the clutch devices into operative engagement, passages controlled by said abutment through which fluid may be released from said chambers to the atmosphere, a valve device having a normal position and being operative on movement therefrom in either direction to cut H communication between said passages and the atmosphere, said valve device being also operative on movement away from the normal position in one direction to supply fluid under pressure to one of saidy flo ber from the normal position to establish communication betweensaid source and said system, and being operative on a further movement of said member from the normal position to establish communication between saidl .pressure regulating valve means and said system.

6. In a control apparatus for a fluid pressure system for controlling the supply and release of uid under pressure to and from said system, a source of fluid under pressure, pressure regulating valve means for supplying fluid under pressure from said source to said system, a selector valve, a member having a normal position for operatingsaid selector valve and said pressure regulating valve means, the selector valve being operative en movement of said member from the normal position to establish communication between said lsource and said system and being operative on a`further movement of said member from the normal position to establish communication between said pressure regulating valve means and said system.

'7. In combination,` a cylinder having a bore therein, a piston reciprocable in said bore, spaced ports communicating with the bore in said cylinder through which uid may be released from the cylinder, the piston controlling communication between the chambers on opposite sides thereof and said ports, and valve means for supplying uid under pressure to the chambers on opposite sides of the piston and for controlling communication between said ports and the atmosphere.

8. In combination, a cylinder having a bore therein, a piston reciprocable in said bore, spaced ports communicating with the bore in said cylinder through which fluid may be released from the cylinder, lthe piston controlling communication between the chambers on opposite sides thereof and said ports, a pressure regulating valve device for supplying fluid under pressure to a passage, and valve means for establishing communication between said passage and the chambers on opposite sides or the said piston and for controlling source to the chambers on opposite sides ofthe piston, for supplying fluid from said passage to said chambers, and for controlling communication between said ports and the atmosphere.

V10. In a control system for a iluid pressure operated device, in combination, a manual operating member having a normal position, valve means operated on movement of said member away from the normal position for suplying fluid under pressure to said device, and a movable abutment subject to the pressure of the fluid supplied by said valve means and opposing movement of said member away from the normal position.

11. In a control system for a pair of fluid pressure operated devices, in combination, a manual operating member having a normal position, valve means operative on movement of said member from the normal position in one direction to supply fluid under pressure to one of said devices, valve means operative on movement of said member from the normal position in the other direction to supplyfluid under pressure to the other of said devices, and a movable abutment subject to the pressure of the fluid supplied to either of said devices and opposing movement of said member from the normal position in either direction.

12. In a control apparatus for a fluid pressure system ,for controlling the supply and release of fluid under pressure to and from said system, a valve device for controlli the supply of fluid under pressure, a valve for controlling communication through which said valve evice supplies fluid under pressure, and a man ally operable member having a normal position, said member being' movable from said normal position for operating said valve and upon a movement of said member relative to said valve device for operating said valve device.

13. In a control apparatus for a iluid pressure system for controlling the supply and release of fluid under pressure to and from said system, a

yvalve device for controlling the supply of fluid under pressure, a fulcrumed manually operable member, elements operatively connecting said valve device with said member disposed at opposite sides of the fulcrum point thereof,vwhereby one element is operated by said member upon movement in one direction and the other element upon movement in the opposite direction, said elements having lost motion connection with said member to permit movement of said member` in one direction relative to each element.

GEORGE C. FARMER.- 

